Control system for controlling an imaging device and a personal computer wherein imaging device control conditions may be freely set between the imaging device and the personal computer

ABSTRACT

A video camera system which can automatically avoid a mismatch that occurs between camera setting values on the PC side and camera setting values on the video camera side immediately after the connection therebetween. A video camera includes a controlled unit capable of being externally controlled in accordance with information inputted from a second data communication node. A control device includes a control unit for outputting the information to control the video camera from a first data communication node, a storage unit for storing at least one preset imaging device control condition, a control condition changing unit for changing the imaging device control condition stored in the storage unit, a detecting unit for detecting whether the control device and the video camera are connected, and an output unit started up in response to a detection signal from the detecting means for reading the imaging device control condition stored in the storage unit and outputting the read control conditions from the first data communication node.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to apparatus and method foroutputting a command from outside of a device to change a control methodof the device to execute an operation different from that actuated byremote control executed by the device's control unit.

[0003] 2. Description of the Related Art

[0004] Hitherto, peripheral devices of a personal computer (referred toas a PC hereinafter), such as a hard disk and a printer, have beenconnected to the PC through a universal interface for small computers,e.g., a digital interface (referred to as a digital I/F) such as a SCSI,for data communication.

[0005] Digital cameras and digital video cameras are also regarded asinput means to a PC and are also peripheral devices. Recently, thetechnology of transferring images (such as still and motion picturespicked up by digital cameras and video cameras) into a PC along withaccompanying voice signals, storing the pictures in a hard disk orediting them in the PC, and then color-printing the pictures using aprinter has been developed and has gained popularity.

[0006] When such image data is outputted from the PC to the printer orto the hard disk, the data is communicated via the above-mentioned SCSIor the like. On that occasion, a versatile digital I/F having a hightransfer data rate, such as the SCSI, is required for sending a largeamount of data.

[0007] However, such conventional digital I/Fs are still inconvenient inmany points because some of them have a low data transfer rate, oremploy large-diameter cables for parallel communication, or havelimitations in type and connecting scheme, or require I/F connectors inthe same number as destinations to be connected.

[0008] Furthermore, in many of the general PCs and digital equipment foruse at home, a connector for connection to a SCSI cable is provided onthe back side of the PC. Such a connector has a relatively large size,and it is rather troublesome to couple the cable to the connector.

[0009] When connecting, to PCs, portable equipment (such as digitalcameras and video cameras) must be connected to connectors on the PCback side at every use, which is very troublesome for users.

[0010] Digital data communication has been used for mutual communicationbetween a PC and such peripheral devices, and has utilized conventionalcommunication techniques. It is however expected in the future that thetypes of devices using digital data will increase, and an improvement ofI/Fs can improve network communication among many interconnected digitaldevices including PC peripheral devices to include digital videocameras, digital storage medium playback apparatuses, etc. If so, suchnetwork communication will be very convenient for users. On the otherhand, since such communication will often transfer an extremely largeamount of data, the use of conventional communication techniques willmake the network crowded and adversely affect the communication betweenother devices in the network.

[0011] In view of the above, a method has been proposed to overcome theproblems encountered in the conventional digital I/Fs, and to employ auniversal digital I/F (e.g., IEEE 1394-1995 High Performance Serial Bus)equipped on each piece of digital equipment in conformity with a unifiedstandard for communication between all the types of digital equipmentincluding PCs and peripheral devices thereof. Thus, the proposed methodintends to realize data communication among devices when a PC, a printerand other peripheral devices, a digital camera, a digital VTR, acamcoder, etc. are connected to each other in the form of a network.

[0012] The IEEE 1394 I/F has several remarkable advantages. Because ofhigh-speed serial communication, though described later in detail, acable is relatively thin and highly flexible, and the connector size ismuch smaller than the case of using a SCSI cable. Further, a largeamount of data such as image information can be transferred at a highspeed along with device control data. In other words, communicationusing the IEEE 1394 I/F is greatly advantageous in that when connectingportable equipment (such as digital cameras and video cameras), theconnection work is much less troublesome for users, and imageinformation can be more easily transferred to PCs.

[0013] The IEEE 1394 serial bus will be described below in more detail.

[0014] (Technical Outline of IEEE 1394)

[0015] With the advent of home digital VTRs and DVD players, it has beenrequired to support data transfers of large amounts of information (suchas video data and audio data) in real time. In order to transfer suchdata in real time, and to input such data into a PC or transfer them toanother piece of digital equipment, an interface is needed which has arequired transfer function and is able to transfer data at a high speed.The IEEE 1394-1995 (High Performance Serial Bus) (referred to as the1394 serial bus hereinafter) is an interface that has been developedfrom the above point of view.

[0016]FIG. 7 shows an example of a network system made up by using 1394serial buses. The network system includes devices A, B, C, D, E, F, Gand H. Twisted pair cables constituting 1394 serial buses are employedto interconnect between A and B, between A and C, between B and D,between D and E, between C and F, between C and G, between C and H. Thedevices A to H comprise, e.g., a PC, a digital VTR, a DVD player, adigital camera, a hard disk, a monitor, etc.

[0017] The devices can be interconnected in a mixed fashion of a daisychain system and a node branch system with a high degree of flexibility.

[0018] Also, each device has its own specific ID, and recognizes the IDsof the other devices which constitute a network devices interconnectedby the 1394 serial buses. Thus, just by connecting two pieces of digitalequipment successively with one 1394 serial bus, one network isconstructed by devices each of which has a relay function. The entirenetwork has the feature of the 1394 serial buses, i.e., a function ofautomatically recognizing network devices, their connection status, etc.based on the plug and play function at the time when the bus cables areconnected to the devices. Further, when some device is removed from ornewly added to the network as shown in FIG. 7, the bus reset isautomatically made to reset the network configuration, and a new networkis formed. This function makes it possible to always set and recognizethe network configuration from time to time.

[0019] The 1394 serial buses allow data transfer rates of 100/200/400Mbps. Devices having higher data transfer rates support the lower datatransfer rates for compatibility between the devices.

[0020] As data transfer modes, there are an asynchronous transfer modefor transferring asynchronous data (referred to as Asynch datahereinafter) such as a control signal, and an isochronous transfer modefor transferring isochronous data (referred to as Iso data hereinafter)such as real-time video data and audio data. The Asynch data and the Isodata are transmitted in a mixed fashion within each cycle (being usually125 μs) with a higher priority given to the Iso data, following transferof a cycle start packet (CSP) which indicates the start of the cycle.

[0021]FIG. 8 shows constituent elements of the 1394 serial bus.

[0022] The 1394 serial bus is of a layered structure in its entirety. Asshown in FIG. 8, the core of hardware components is a 1394 serial buscable. A connector of the cable is connected to a connector port, and aphysical layer and a link layer exist as other hardware components at alevel higher than the connector port.

[0023] Those two hardware components essentially constitute an interfacechip. The physical layer executes coding, control related to theconnector, etc, and the link layer executes packet transfer, control ofcycle time, etc.

[0024] A transaction layer (as one of the firmware components) managesdata to be subjected to transfer (transaction), and issues commands suchas Read and Write. A serial bus management (as the other firmwarecomponent) manages connection status of the devices connected to thebus, IDs, and the network configuration.

[0025] The above-described hardware and firmware components essentiallyconstruct the 1394 serial bus.

[0026] An application layer (as a software component) varies dependingon the software used. The application layer specifies a manner ofplacing data on the interface, and is specified by a protocol such as anAV protocol.

[0027] The 1394 serial bus is constructed as described above.

[0028] Next, FIG. 9 shows an address space in the 1394 serial bus.

[0029] The devices (nodes) connected to the 1394 serial bus are eachgiven with its own specific 64-bit address, without exceptions. The nodeaddresses are stored in a ROM so that each device can always recognizeits own and other addresses, and can perform communication with apartner designated.

[0030] Addressing of the 1394 serial bus conforms with the IEEE 1212standards. Specifically, the node address is set as follows. The first10 bits are used for designating the bus number, and the next 6 bits areused for designating the node ID number. The remaining 48 bits representan address width allocated to the device, and can be used as a specificaddress space. The last 28 bits represent a specific data area in whichinformation necessary for identifying the device and designating serviceconditions thereof are stored.

[0031] The technical outline of the IEEE 1394 serial bus has beendescribed above.

[0032] The technical features of the IEEE 1394 serial bus will now bedescribed in more detail.

[0033] (Electrical Specifications of IEEE 1394 Serial Bus)

[0034]FIG. 10 shows a section of the 1394 serial bus cable.

[0035] In the connecting cable of the 1394 serial bus, power lines canbe disposed in addition to two sets of twisted signal line pairs. Withthe provision of the power liens, power can be supplied to, e.g., adevice having no power supply, or to a device having a voltage lowereddue to a failure.

[0036] Alternatively, a simplified connecting cable may exclude powerlines under conditions which restrict devices to which the cable may beconnected.

[0037] Power supplied through the power lines is specified to have avoltage of 8 to 40 V and a maximum DC current of 1.5 A.

[0038] (DS-Link Coding)

[0039]FIG. 11 is a chart for explaining a DS-Link coding method of adata transfer format employed for the 1394 serial bus.

[0040] The 1394 serial bus employs a DS-Link (Data/Strobe-Link codingmethod. The DS-Link coding method is suitable for high-speed serial datacommunication, and requires two signal lines. Of a pair of twistedlines, one line serves to transmit primary data, and the other lineserves to transmit a strobe signal.

[0041] On the receiving side, a clock can be reproduced by taking theexclusive logical sum of data and strobe.

[0042] The merits of employing the DS-Link coding method are describedbelow. Transfer efficiency is higher than other serial data transfermethods. No need of a PLL circuit reduces the circuit scale of acontroller LSI. When there is no data to be transferred, it is notrequired to transmit information indicating an idle state. Accordingly,a transceiver circuit of each device can be brought into a sleep state,and power consumption can be reduced.

[0043] (Bus Reset Sequence)

[0044] In the 1394 serial bus, the devices (nodes) connected to the busare each given a specific node ID, and recognized as one of the nodes ofa network configuration.

[0045] When it is required to recognize a new network configuration upona change of the network configuration, e.g., upon the number of nodesbeing increased or reduced due to insertion or removal of a node or apower-on/off in the node, each node having detected such a changetransmits a bus reset signal on the bus, and goes into a mode forrecognizing a new network configuration. At this time, such a change isdetected by sensing a change of the bias voltage on a 1394 port board.

[0046] At soon as one node transmits a bus reset signal and the physicallayer of another node receives the bus reset signal, the occurrence of abus reset is indicated from the physical layer to the link layer, andthe bus reset signal is further transmitted to still another node. Afterall the nodes have finally received the bus reset signal, the bus resetis started up.

[0047] The bus reset is started up when a hardware change, such asinsertion or removal of the cable or an abnormal condition of thenetwork, is detected as described above, or when a command is directlyissued to the physical layer under host control in accordance with theprotocol.

[0048] Also, data transfer is temporarily suspended upon the start-up ofthe bus reset, and is held in a standby state during the suspension.After the suspension, data transfer is restarted under a new networkconfiguration.

[0049] The bus reset sequence has been described above.

[0050] (Node ID Determining Sequence)

[0051] After the bus reset, the nodes start the operation for allocatingIDs to themselves to construct a new network configuration. A generalsequence from the bus reset to the determination of node IDs will bedescribed below with reference to flowcharts of FIGS. 19, 20 and 21.

[0052] The flowchart of FIG. 19 shows a sequence of steps executed onthe bus from the bus reset until the node IDs are determined to permitstart of data transfer.

[0053] First, in step S101, it is always monitored whether a bus resetoccurs in the network. If the bus reset occurs due to, e.g.,power-on/off in the node, the processing goes to step S102.

[0054] In step S102, parent-child relation is declared between nodes,which are directly connected to each other, for determining theconnection status of a new network from the reset state of the network.If parent-child relations are decided between all the nodes in stepS103, one root is decided in step S104. Until parent-child relations aredecided between all the nodes, the declaration of parent-child relationin step S102 is repeated and the root is not decided.

[0055] If the root is decided in step S104, the processing goes to stepS105 in which the node ID setting operation is carried out to allocateIDs to the nodes. The node ID setting operation is repeated to set thenode IDs in a predetermined node sequence until all the nodes are giventheir own IDs. If all the nodes are completely given the IDs in stepS106, this means that the new network configuration has been recognizedby all of the nodes. In step S107, therefore, the bus comes into a statecapable of performing data transfer between the nodes, and the datatransfer is started.

[0056] Subsequent to the state of step S107, the bus is brought againinto the mode of monitoring the occurrence of the bus reset in thenetwork. If the bus reset occurs, the node ID setting operation fromstep S101 to step S106 is repeated.

[0057] The flowchart of FIG. 19 has been described above. FIGS. 20 and21 are flowcharts showing in more detail a process from the bus reset tothe determination of the root and a process from the determination ofthe root to the end of the ID setting, respectively, in the flowchart ofFIG. 19.

[0058] The flowchart of FIG. 20 will be first described.

[0059] If the bus reset occurs in step S201, the network configurationis once reset.

[0060] It is always monitored in step S201 whether a bus reset occurs inthe network.

[0061] Then, in step S202, a flag indicating that the device is a leaf(node) is set in each such device as a first step of the operation forrecognizing the connection status of the reset network. Thereafter, instep S203, it is checked how many ports provided in each device itselfare connected to other nodes.

[0062] The number of ports not yet defined (i.e., for which aparent-child relation is not yet decided) is checked in step S204 forstarting the declaration of parent-child relations depending on thenumber of ports obtained in step S204. Immediately after the bus reset,the number of ports is equal to the number of ports not yet defined.However, the number of ports not yet defined, which is detected in stepS204, varies as the decision of parent-child relation progresses.

[0063] Immediately after the bus reset, the node for which parent-childrelation can be first declared is limited to only a leaf. Whether thenode is a leaf can be recognized by confirming the number of portschecked in step S203. In step S205, the leaf declares “I am a child anda partner is a parent” for the node to which the leaf is connected,thereby ending the process.

[0064] For the node which has been recognized in step S203 as having aplurality of ports and being a branch, the number of not-yet-definedports >1 is determined in step S204 immediately after the bus reset.Accordingly, the processing goes to step S206 in which a flag indicatinga branch is set. Then, in step S207, the node waits for accepting“parent” based on the declaration of parent-child relation from theleaf.

[0065] For the branch having accepted in step S207 the declaration ofparent-child relation from the leaf, the control flow returns to stepS204 to confirm the number of ports not yet defined. If the number ofports not yet defined is one, this means that the declaration of “I am achild and a partner is a parent” in step S205 can be made for the nodewhich is connected to the remaining port. For the branch having two ormore ports not yet defined as a result of the second or laterconfirmation in step S204, the processing goes to step S207 again towait for accepting “parent” based on the declaration of parent-childrelation from the leaf or another branch.

[0066] Finally, if the number of ports not yet defined becomes zero as aresult of the confirmation in step S204 for any one branch or a leaf asan exceptional case (because the leaf has not operated so fast though itcan declare “child”), this means that the declaration of parent-childrelation is completed for the entire network. For only one node forwhich the number of ports has not yet been confirmed to be zero (i.e.,for which all ports have been decided as parent ports), a flagindicating a root is set in step S208. Then, in step S209, that node isrecognized as a root.

[0067] In this way, the process from the bus reset to the declaration ofparent-child relation for all the nodes in the network, shown in FIG.20, is completed.

[0068] Next, the flowchart of FIG. 21 will be described.

[0069] Since flag information indicating a leaf, branch or root is setfor each node in the sequence of steps shown in FIG. 20, the nodes areclassified in step S301 based on the flag information.

[0070] In the operation of allocating IDs to the nodes, the node whichcan first set an ID is a leaf. IDs are set by allocating numbersincreasing from zero (i.e., node number=0-) in the order of leaf, branchand root.

[0071] In step S302, the number N (N is a natural number) of leavespresent in the network is set. After that, in step S303, each leafrequests the root to give an ID to the leaf. If there are a plurality ofrequests, the root carries out arbitration between the requests(operation of selecting one request) in step S304. In step S305, an IDnumber is given to one node which has won the arbitration, and a failurein ID setting is provided to the nodes which have been defeated in thearbitration. Each leaf which has failed in acquiring ID issues an IDrequest again in step S306, followed by repeating the steps mentionedabove. In step S307, the leaf which has succeeded in acquiring an IDnumber broadcasts its own self-ID packet to all the nodes.

[0072] The self-ID packet contains ID information of the node, thenumber of ports of the node, the number of ports already connected,information indicating whether each port is a parent or a child,information indicating whether the node has an ability allowing the nodeto serve as a bus manager (if the node has such an ability, a contenderbit in the self-ID packet is set to 1, and if the node does not havesuch an ability, the contender bit is set to 0), etc.

[0073] The ability allowing the node to serve as a bus manager meanssuch an ability that the node can perform the four kinds of busmanagement set forth below.

[0074] (1) Bus Power Management

[0075] The node can determine whether each of the devices on the networkconstructed as shown in FIG. 7 is required to be supplied with powerthrough the power lines in the connecting cable, or whether each deviceis supplied with power independently. Also, the node can manage the timewhen power is supplied to each device.

[0076] (2) Keeping of Speed Map

[0077] The node can maintain communication speed information of thedevices on the network.

[0078] (3) Keeping of Network Structure (Topology Map)

[0079] The node can maintain information regarding a tree structure ofthe network as shown in FIG. 12.

[0080] (4) Optimization of Bus Based on Information Obtained fromTopology Map

[0081] The node (which is selected as a bus manager throughlater-described procedures) performs the bus management in the entirenetwork.

[0082] Also, the node having the ability to serve as a bus manager(i.e., the node broadcasting the self-ID packet with-the contender bitset to 1) stores information in the self-ID packet broadcast from eachof the remaining nodes, and other information such as communicationspeeds. When that node is selected as a bus manager, it constructs aspeed map and a topology map based on the stored information.

[0083] After one node has broadcast the node ID information, the numberof remaining leaves is counted down by one in step S308. If the numberof remaining leaves is not less than one in step S309, theabove-described process from the operation of requesting ID in step S303is repeated. Finally, if all the leaves have broadcast the node IDinformation, N=0 is satisfied in step S309 and the processing goes to anID setting process for branches.

[0084] The ID setting of branches is performed in a like manner to theID setting of leaves.

[0085] First, in step S310, the number M (M is a natural number) ofbranches present in the network is set. After that, in step S311, eachbranch requests the root to give an ID to the branch. In response torequests, the root carries out arbitration between the requests in stepS312. ID numbers increasing from the last number given to the leaf areallocated to respective branches successively starting from the branchwhich has first won the arbitration. In step S313, the root provides theID information (or a failure result) to each of the branches havingrequested IDs. Each branch which has failed in acquiring an ID issues anID request again in step S314, followed by repeating the steps mentionedabove.

[0086] In step S315, the branch which has succeeded in acquiring the IDnumber broadcasts its own self-ID packet to all the nodes. After onenode has broadcast the node ID information, the number of remainingbranches is counted down by one in step S316. If the number of remainingbranches is not less than one in step S317, the above-described processfrom the operation of requesting an ID in step S311 is repeated untilall the branches finally broadcast the node ID information. If all thebranches acquire the node IDs, M=0 is satisfied in step S317, therebyending the branch ID setting mode.

[0087] At a point in time after the above branch ID setting mode isended, the node which has not yet acquired ID information is only aroot. Therefore, a number next to the largest among the numbers havingbeen already allocated to the other nodes is set as the ID number of theroot in step S318, and the root broadcasts its own self-ID packet instep S319.

[0088] Through the process described so far, it becomes apparent whichnode has the ability to serve as a bus manager. If a plurality of nodesfinally have an ability to serve as a bus manager, the node having thelargest ID number is selected as the bus manager.

[0089] When the root has the ability to serve as the bus manager, theroot is selected as the bus manager because its ID number is the largestin the network. When the root does not have the ability to serve as thebus manager, the root which has the second largest ID number (ascompared with that of the root and the contender bit in the self-IDpacket is set to 1) is selected as the bus manager. Which node has beenselected as the bus manager can be ascertained by all the nodes as amatter recognized by all of them because each node broadcasts its ownself-ID packet at the time of acquiring the ID number in the processshown in FIG. 21 and each node keeps the information in the self-IDpackets broadcast from the other nodes.

[0090] The procedures for setting IDs of all the nodes and the busmanger after determining the parent-child relation for each node, asshown in FIG. 21, are thus ended.

[0091] Next, the operation in the actual network shown in FIG. 12 willbe described, by way of example, with reference to FIG. 12.

[0092] The network shown in FIG. 12 has a hierarchical structure suchthat the nodes A and C are directly connected to the (root) node B at alevel lower than the latter, the node D is directly connected to thenode C at a level lower than the latter, and the nodes E and F aredirectly connected to the node D at a level lower than the latter. Theprocedures for deciding the hierarchical structure, the root node, andthe node IDs will be described below.

[0093] After the bus reset, the declaration of parent-child relation isfist made between ports of the nodes, which are directly connected toeach other, for recognizing the connection status of each node. Theparent-child relation means that the parent side lies at a higher leveland the child side lies at a lower level in the hierarchical structure.

[0094] In the network of FIG. 12, the node which has first declaredparent-child relation after the bus reset is the node A. Basically, thedeclaration of parent-child relation can be started from a node (calleda leaf) in which only one port is connected to another node. Such a nodecan detect by itself that only one port thereof is connected to anothernode. Upon detecting the fact, the node recognizes that it is positionedat the end of the network. Then, the parent-child relation issuccessively decided from the node which has finished the recognizingoperation at the earliest timing. The port of the node which hasdeclared a parent-child relation (e.g., the node A between A and B) isset to a child, whereas the port of the partner node (the node B) is setto a parent. As a result, the nodes A and B, the nodes E and D, and thenodes F and D are decided respectively as a child and a parent.

[0095] The declaration process then moves up a rank. The declaration ofparent-child relation is likewise made toward an upper level nodesuccessively from one of nodes having a plurality of ports connected(called a branch) which has earlier accepted the parent-child relationfrom another node. In the network of FIG. 12, after the parent-childrelation has been decided between D and E and between D and F, the nodeD first declares parent-child relation to the node C. As a result, thenodes D and C are decided respectively as a child and a parent.

[0096] After accepting the declaration of parent-child relation from thenode D, the node C declares parent-child relation to the node B which isconnected to the other port of the node C. As a result, the nodes C andB are decided respectively as a child and a parent.

[0097] As described above, the hierarchical structure shown in FIG. 12is constructed, and the node B, for which all ports thereof connected tothe other nodes have been finally decided as parents, is decided as aroot node. One network system includes only one root.

[0098] While the node B is decided as a root node in FIG. 12, the rootnode could possibly shift to another node if the node B (having acceptedthe declaration of a parent-child relation from the node A) declares aparent-child relation to another node at an earlier time. In otherwords, any node has the possibility to become the root node depending onthe timing at which its declaration of a parent-child relation istransmitted, and a certain node is not always decided as the root nodeeven in the same network configuration.

[0099] After deciding the root node, the network enters the mode ofdeciding node IDs. In this mode, each node provides its own node ID toall of the other nodes (broadcasting function).

[0100] Self-ID information of the node contains the self-node number,information regarding the position at which it is connected, the numberof ports possessed by the node, the number of ports connected to otherports, information regarding parent-child relation for each port, etc.

[0101] The procedures for allocating the node ID numbers can be startedfrom one of nodes (leaves) each having only one port connected toanother node. The node ID numbers=0, 1, 2, . . . are then allocated insequence to those nodes.

[0102] Upon receiving the node ID number, each node broadcasts self-IDinformation containing the node ID number to all of the other nodes.This permits the other nodes to recognize that the broadcast ID numberhas been already allocated.

[0103] After all the leaves have acquired their own node IDs, the modeproceeds to the operation of deciding IDs of branches, and increasingnode ID numbers subsequent to the largest number given to the last leafare allocated to the branches successively. As with the leaves, uponreceiving the node ID number, each branch broadcasts self-ID informationin sequence with all of the other nodes. Finally, the root nodebroadcasts self-ID information. Thus the root always has the largestnode ID number.

[0104] As described above, node ID numbers are allocated to all thenodes in the entire the hierarchical structure, the networkconfiguration is reconstructed, and the bus initialization is completed.

[0105] (Arbitration)

[0106] In the 1394 serial bus, arbitration for the right of using thebus is always performed prior to data transfer. The 1394 serial busconstructs such a logical bus type network that each of devicesindividually connected to the bus relays a signal transferred to it,whereby the same signal is transmitted to all the devices in thenetwork. Accordingly, arbitration is essential for the purpose ofavoiding collision between packets. The arbitration enables only onenode to transfer a packet at a certain time.

[0107] The arbitration will be described below with reference to FIG.13A which illustrates a process of requesting the right of using thebus, and FIG. 13B which illustrates a process of permitting/rejectingthe use of the bus.

[0108] Upon the start of arbitration, one or several nodes issuerequests the right of using the bus toward the corresponding parentnodes. In FIG. 13A, the nodes C and F are nodes issuing requests for theright of using the bus. The parent node having received the request(i.e., the node A in FIG. 13A) further issues (relays) a request for theright of using the bus toward the succeeding parent node. Those requestsfinally reach the root which performs the arbitration.

[0109] The root node having received the requests for the right of usingthe bus decides which node is permitted to use the bus. The arbitrationprocess can be executed by only the root node, and the node which haswon the arbitration is given with the right of using the bus. In FIG.13B, the use of the bus is permitted to the node C, and the node F isrejected from using the bus. A DP (Data Prefix) packet is sent to thenode which has been rejected in the arbitration, thereby informing thenode that the use of the bus has been rejected. The request for theright of using the bus, which has been issued from the rejected node, isleft standing to wait for the next arbitration.

[0110] The node, which has won the arbitration and has gained permissionfor the use of the bus, can start data transfer subsequently.

[0111] A sequence of the arbitration steps will now be described withreference to a flowchart of FIG. 22.

[0112] When the node starts data transfer, the bus must be in an idlestate for enabling the data transfer to start. Whether a preceding datatransfer is ended and the bus is in an idle state at present can berecognized by checking the lapse of a predetermined idle time gap length(e.g., a subaction gap) which is uniquely set for each transfer mode. Ifthe subaction gap has lapsed, each node determines that the node itselfcan start the data transfer.

[0113] In step S401, it is determined whether the predetermined gaplength corresponding to data to be transferred (such as Asynch data orIso data) is obtained. Unless the predetermined gap length is obtained,any node cannot request the right of using the bus that is needed forstarting the data transfer. Accordingly, each node waits until thepredetermined gap length is obtained.

[0114] If the predetermined gap length is obtained in step S401, it isdetermined in step S402 whether there is data to be transferred. If so,the processing goes to step S403 in which each node issues a request forthe right of using the bus to the root for securing the bus to start thedata transfer. At this time, a signal representing the request for theright of using the bus is transmitted so as to finally reach the rootafter being relayed from one to another device in the network, as shownin FIG. 13. If there is no data to be transferred in step S402, the nodegoes into a standby state.

[0115] Then, if the root receives in step S404 one or more requests forthe right of using the bus issued in step S403, the root checks thenumber of nodes requesting the use of the bus in step S405. If thenumber of nodes requesting the use of the bus is equal to one in stepS405 (i.e., if only one node has issued the request for the right ofusing the bus), the right of using the bus immediately thereafter isgranted to that node. If the number of nodes requesting the use of thebus is more than one in step S405 (i.e., if a plurality of nodes haveissued requests for the right of using the bus), the root performs aarbitration process in step S406 for deciding one node which is allowedto use the bus. The arbitration process is made impartial so thatpermission is not given to the same node at every time, but the right ofusing the bus is equally permitted to all the nodes.

[0116] In step S407, the plurality of nodes requesting the use of thebus in step S406 are classified into one node which has gained the rightof using the bus as a result of the arbitration performed by the root,and the other nodes which have been rejected in the arbitration. Then,in step S408, the root transmits a permission signal to one node whichhas gained the right of using the bus as a result of the arbitration, orthe node which has gained the right of using the bus without thearbitration because the number of nodes requesting the use of the bus isequal to one in step S405. Immediately after receiving the permissionsignal, the node starts the transfer of data (a packet to betransferred). In step S409, the root transmits a DP (Data Prefix) signalindicating a failure in the arbitration to each of the nodes which hasbeen rejected in the arbitration in step S406 and rejected from usingthe bus. The node having received the DP packet returns to step S401,and then waits until the predetermined gap length is obtained, followedby issuing the requests for the right of using the bus to start the datatransfer.

[0117] The arbitration process has been described above with referenceto the flowchart of FIG. 22.

[0118] (Asynchronous Transfer)

[0119] In asynchronous transfer, data is transferred in an asynchronousmanner. FIG. 14 shows state transitions over time in the asynchronoustransfer mode. The first subaction gap in FIG. 14 represents an idlestate of the bus. At the time when the idle time has reached a certainvalue, the node desiring to start the data transfer determines that thebus is available, following which the arbitration is executed to securethe bus.

[0120] After gaining permission of the use of the bus as a result of thearbitration, the data transfer is executed in the form of a packet.After the data transfer, the node having received the data responds tothe data transferred to it by sending back an ACK (return code forconfirming reception) as a result of the reception after a short gapcalled the ACK GAP, or by transmitting a response packet, whereupon thepacket transfer is completed. The ACK comprises information of 4 bitsand checksum of 4 bits. The ACK includes information indicating whetherthe destination node of the transmission has succeeded in receiving thedata, or whether it is in a busy state or a pending state, and is sentback to the source node at once.

[0121] Next, FIG. 15 shows an example of a packet format for use in theasynchronous transfer mode.

[0122] A packet comprises a data portion, a data CRC for errorcorrection, and a header portion. The destination node ID, the sourcenode ID, the length of transferred data, various codes, etc. are writtenin the header portion as shown in FIG. 15, and then transferred.

[0123] Also, the asynchronous transfer is communication carried out inone-to-one relation from some node to a partner node. A packettransferred from the source node is routed to all the nodes in thenetwork, but the node ignores the packet having an address other thanbelonging to itself. Accordingly, the packet is read by only onedestination node.

[0124] The asynchronous transfer has been described above.

[0125] (Isochronous Transfer)

[0126] In isochronous transfer, data is transferred in an isochronousmanner. The isochronous transfer, which can be the biggest feature ofthe 1394 serial bus, is a transfer mode suitable for multimedia such asvideo data and voice data, particularly, which require real-timetransfer.

[0127] Also, while the asynchronous transfer is a one-to-one relationtransfer, the isochronous transfer renders a packet to be transferredfrom one source node equally to all the other nodes with thebroadcasting function.

[0128]FIG. 16 shows state transition over time in the isochronoustransfer mode.

[0129] The isochronous transfer is executed with certain time intervalson the bus. This time interval is called an isochronous cycle. The timeof one isochronous cycle is 125 μs. A cycle start packet indicates thestart time of each cycle, and serves to perform time adjustment for eachnode. The cycle start packet is transmitted by a node called a cyclemaster. After a predetermined idle period (subaction gap) has elapsedsubsequent to the end of packet transfer in the preceding cycle, thecycle master transmits the cycle start packet indicating the start ofthe current cycle. The time interval at which the cycle start packet istransmitted is 125 μs.

[0130] Also, as indicated by channels A, B and C in FIG. 16, pluraltypes of packets can be separately transferred in one cycle byallocating channel IDs to those packets respectively. This enablespackets to be transferred in real time between a plurality of nodes atthe same time. The node on the receiving side takes in data of only thepacket assigned with the channel ID that is desired by the node itself.The channel ID does not represent the address of the destination oftransmission, but merely indicates a logical number (or character) givento each packet data for discrimination. Therefore, when some packet istransmitted, the packet is broadcast so that it is routed from onesource node to all of the other nodes.

[0131] Prior to transmitting a packet in the isochronous transfer mode,arbitration is performed as with the asynchronous transfer mode.However, because the isochronous transfer mode is not a one-to-onecommunication (unlike the asynchronous transfer mode), there is no ACK(return code for confirming reception) in the isochronous transfer mode.

[0132] Further, an ISO GAP (isochronous gap) shown in FIG. 16 representsan idle period necessary for recognizing that the bus is in an idlestate, prior to starting the isochronous transfer. At the time when thepredetermined idle period has elapsed, the node desiring to start theisochronous transfer determines that the bus is in an idle state,following which an arbitration is conducted before the packet transfercan be executed.

[0133] Next, FIG. 17 shows an example of a packet format for use in theisochronous transfer mode.

[0134] Various packets are separated into channels and each comprises adata portion, a data CRC for error correction, and a header portion. Thelength of transferred data, the channel No., various codes, a header CRCfor error correction, etc. are written in the header portion as shown inFIG. 17, and then transferred.

[0135] The isochronous transfer mode has been described above.

[0136] (Bus Cycle)

[0137] In actual transfer on the 1394 serial bus, the isochronoustransfer and the asynchronous transfer can be executed in mixed fashion.FIG. 18 shows transfer state transitions on the bus over time when theisochronous transfer and the asynchronous transfer are executed in mixedfashion.

[0138] The isochronous transfer is executed in preference to theasynchronous transfer. The reason is that after the cycle start packet,the isochronous transfer can be started with a shorter gap length(isochronous gap) than the gap length (subaction gap) of an idle periodrequired for starting the asynchronous transfer. Accordingly, executionof the isochronous transfer is given with higher priority than that ofthe asynchronous transfer.

[0139] In a general bus cycle shown in FIG. 18, the cycle start packetis transferred from the cycle master to each node at the start of acycle #m. Upon receiving the cycle start packet, each node performs timeadjustment. After waiting for the predetermined idle period (isochronousgap), the node which is going to execute the isochronous transfer entersarbitration and then starts the packet transfer. In FIG. 18, channels e,s and k are transferred by isochronous transfer in sequence.

[0140] The above process from the arbitration to the packet transfer isrepeated in times corresponding to the number of channels given.Subsequently, when the isochronous transfer in the cycle #m iscompleted, the asynchronous transfer can be started.

[0141] Upon the idle time reaching the end of the subaction gapnecessary for starting the asynchronous transfer, the node which isgoing to execute the asynchronous transfer determines that it may enterthe arbitration.

[0142] However, the asynchronous transfer can be started only when thesubaction gap necessary for starting the asynchronous transfer isobtained during a period from the end of the isochronous transfer to thetime (CYCLE SYNCH) at which the next cycle start packet is transferred.

[0143] In the cycle #m shown in FIG. 18, three channels are firsttransferred by isochronous transfer, and two packets (packets 1 and 2)are then transferred by asynchronous transfer (including ACK). Thetransfer in the cycle #m is ended by sending the asynchronous packet 2because the time (CYCLE SYNCH) to start the next cycle (m+1) is reachedafter the asynchronous packet 2.

[0144] If the time (CYCLE SYNCH) to transmit the next cycle start packetis reached during the operation of the asynchronous or isochronoustransfer, the operation is not forcibly suspended, and the cycle startpacket for the next cycle is transmitted after waiting for the idleperiod subsequent to the pending transfer. In other words, if one cyclecontinues over 125 μs, it is assumed that the next cycle is contractedfrom the reference period, i.e., 125 μs, by an amount corresponding tothe extension of the preceding cycle. Thus the isochronous cycle can beextended and contracted from the reference period of 125 μs.

[0145] In order to maintain real-time transfer, however, theasynchronous transfer is always executed in each cycle if necessary. Dueto contraction of the cycle time, the asynchronous transfer may bedelayed to the next or subsequent cycle.

[0146] The above-described process, including such delay information, ismanaged by the cycle master.

[0147] (WWID (World Wide Unique ID))

[0148] According to the 1394 serial bus standards, each nodeincorporates a configuration ROM for expressing its own functions. FIG.23 shows a part of the configuration ROM.

[0149] Referring to FIG. 23, IDs stored in addresses from FFFFF000040Cto FFFFF0000410 comprise a vendor ID 2301 of three bytes and chip IDs2302, 2303 of five bytes. The vendor ID 2301 is an ID acquired by eachvendor as a result from applying for the ID from the IEEE, and containsinformation indicating, e.g., the name of each vendor. The chip IDs2302, 2303 are allocated at the vendor's discretion, and are set to aunique ID for each node. There is hence no ID that is the same as theunique ID (2301-2303) of each node.

[0150] The above ID (2301-2303) uniquely allocated for each node iscalled a World Wide Unique ID (referred to a WWUID hereinafter). Eachnode on a network constructed with the IEEE 1394 serial bus can know theWWUID by reading the IDs at the addresses from FFFFF000040C toFFFFF0000410 in the configuration ROM of a device which is connected tothe bus and has an objective node ID.

[0151] The IEEE 1394 serial bus has been described above.

[0152] As seen from the above description, the IEEE 1394 I/F has variousadvantages overcoming the inconveniences experienced in conventionaldata communication systems. In particular, since the IEEE 1394 I/F cantransfer a large amount of data, such as image information, at a highspeed along with device control data, using the IEEE 1394 I/F makes itpossible to construct a new system wherein an imaging device representedby a video camera is controlled by a PC.

[0153] Stated otherwise, the present invention intends to construct asystem for controlling a camera control unit originally incorporated inan imaging device, by outputting an operation command or instructingsome change of a control method from a PC to thereby permit the imagingdevice to execute an operation different from that commanded by remotecontrol, or some change of the control method executed by the cameracontrol unit originally incorporated in the imaging device, to therebycarry out an operation to perform a special operation in the videocamera being controlled.

[0154]FIG. 24 shows an example of screen display of an application(referred to a camera setting application) for operating and controllinga camera from a PC as mentioned above.

[0155] The camera setting application operates in a condition where a PC2501 and a video camera 2505 are connected to each other by a 1394serial bus 2504, as shown in FIG. 25. The user can freely change thesetting of various control parameters in the video camera 2505, such astint, color gain, f-stop number and shutter speed, by using a keyboard2503 or a pointing device 2502. For example, when a shutter speedchanging lever 2405 is moved to the left or right with the pointingdevice 2502, a setting value corresponding to the lever position istransmitted from the PC 2501 to the video camera 2505 via the 1394serial bus 2504. The video camera 2505 can actually change the shutterspeed by storing the setting value at a predetermined location in aninternal memory.

[0156] Here, the 1394 serial bus can transmit and receive both imagedata and a command group (CTS) for controlling a partner device at thesame time. Therefore, when the video camera 2505 transmits image data tothe PC 2501, the user can confirm the camera image on a screen of the PC2501 in real time. A camera image display window 2401 on the camerasetting application screen of FIG. 25 is a screen for displaying in realtime an image transmitted from the video camera 2505. In other words, bychanging the setting of control parameters of the video camera from thePC in such a manner as described above, the user can immediately confirma result of the change on the camera image display window 2401.

[0157] The illustrated conventional example includes several kinds ofcamera control parameters which are changeable, but there exist manyother parameters which can be set from the PC. FIG. 28 shows examples ofcommands transmitted from the PC for changing the parameters.

[0158] Although the camera setting application carries out theabove-described function in the condition where the video camera 2505and the PC 2501 are connected to each other as shown in FIG. 25, thereis a simulation mode in the camera setting application. The simulationmode means such a function that the PC simulates an optimum image byitself alone by changing the setting of camera control parameters withrespect to an original image picked up by the camera.

[0159] The simulation mode will be briefly described below withreference to FIGS. 26 and 27.

[0160]FIG. 26 shows an example in which a sunset scene shot by the useris displayed on the camera image display window 2401 in the simulationmode. An operating mode 2407 of the camera setting application isselected to “SIMULATION” by the pointing device. In this condition, thecamera setting application stops the PC from taking in image informationfrom the video camera, and an image, which is simulated as describedlater, is continuously displayed on the camera image display window2401.

[0161] In the case of shooting the setting sun, the user generallydesires to produce an image rich in red. With usual auto-setting of thevideo camera, however, an auto-white balancing function is operated tosuppress a component of red color to become as close as possible towhite. Accordingly, red color of the taken-in image is lightened, and asunset scene cannot be shot as desired. Then, the user changes thesetting of camera control parameters on the camera setting applicationscreen, such as tint 2402, color gain 2403, f-stop number 2404, shutterspeed 2405, and quakeproof on/off 2406, by using the pointing device orthe keyboard on the PC. For example, the tint 2402 is set nearer to theblue side in an initial image, but the tint setting is changed to comecloser to the red side for emphasizing the red color of the sunset.Corresponding to the lever position of the tint 2402 to be changed, thecamera setting application changes the camera control parameters so thatthe same image on the camera image display window 2401 has a tintcorresponding to the change in the parameter. Thus, the image displayedon the camera image display window 2401 has the tint emphasized in red.Likewise, the user can change the setting of the other parameters, suchas the color gain 2403 and the f-stop number 2404, in accordance withhis/her preference while confirming a simulated image on the cameraimage display window 2401. Finally, the user can obtain the optimumcamera setting as shown in FIG. 27.

[0162] Further, the optimum camera setting can be stored as a file inthe memory within the PC by manipulating a file menu 2408 on a task bar.The stored setting can be transmitted to the video camera when it isconnected to the PC again, enabling the video camera to be set to “anoptimum condition for shooting the sunset”.

[0163] The above-described related art however has the followingproblem. Even with the video camera being not connected, the optimumcamera setting parameters can be decided based on simulation.Accordingly, when the video camera is connected to the PC later, thereoccurs a discrepancy between setting values in the video camera andvalues changed on the PC. As a result, the operation of the camerasetting application and the actual operation of the video camera can notbe matched with each other.

SUMMARY OF THE INVENTION

[0164] The present invention has been made in the view of the problemset forth above, and its object is, in a camera setting system wherein acontrol device, such as a PC, and a video camera are connected to eachother, to automatically avoid a mismatch between setting values on thePC side and camera setting values in the video camera which occursimmediately after the connection therebetween, immediately after the PCand the video camera are connected again.

[0165] Another object of the present invention is, in a camera settingsystem wherein a control device, such as a PC, and a video camera areconnected to each other, and particularly in a camera setting systemhaving a simulation function, to automatically avoid a mismatch betweensetting values on the PC side, which have been changed upon execution ofsimulation, and unchanged setting values in the video camera,immediately after the PC and the video camera are connected again.

[0166] Still another object of the present invention is, in a camerasetting system wherein a control device, such as a PC, and a pluralityof video cameras are connected to each other, to avoid a mismatchbetween setting values on the PC side, which correspond to a particularone of the video cameras, and camera setting values in the particularvideo camera, immediately after the connection therebetween.

[0167] Still another object of the present invention is, in a camerasetting system wherein a control device, such as a PC, and a pluralityof video cameras are connected to each other, and particularly in acamera setting system having a simulation function, to automaticallyavoid a mismatch between setting values on the PC side, which have beenchanged upon execution of simulation, and unchanged setting values in aparticular one of the video cameras, immediately after the PC and theparticular video camera are connected again.

[0168] Still another object of the present invention is, in a camerasetting system wherein a control device, such as a PC, and a pluralityof video cameras are connected to each other, to surely select aparticular one of the video cameras by utilizing IDs specific to thevideo cameras, and to automatically avoid a mismatch between settingvalues on the PC side, which have been changed and correspond to theselected video camera, and camera setting values in the selected videocamera.

[0169] Still another object of the present invention is, in a camerasetting system wherein a control device, such as a PC, and a videocamera are connected to each other, to avoid a mismatch between adisplay of setting values on the PC side and camera setting values inthe video camera, immediately after the connection therebetween.

[0170] Still another object of the present invention is, in a camerasetting system wherein a control device, such as a PC, and a pluralityof video cameras are connected to each other, to avoid a mismatchbetween a display of setting values on the PC side, which correspond toparticular one of the video cameras, and camera setting values in theparticular video camera, immediately after the connection therebetween.

[0171] Still another object of the present invention is, in a camerasetting system wherein a control device, such as a PC, and a pluralityof video cameras are connected to each other, to surely select aparticular one of the video cameras by utilizing IDs specific to thevideo cameras, and to avoid a mismatch between a display of settingvalues on the PC side, which correspond to the particular video camera,and camera setting values in the selected video camera, immediatelyafter the connection therebetween.

[0172] Still another object of the present invention is to produce analarm display when setting values on the PC side (which correspond to aparticular video camera) differ from camera setting values in a selectedvideo camera.

[0173] To solve the above-described problem and to achieve theabove-mentioned objects, the present invention provides an imagingdevice system comprising a control device having a first datacommunication node, and an imaging device having a second datacommunication node connected to the first data communication node in amutually communicable manner. The imaging device includes a controlledunit capable of being externally controlled in accordance withinformation inputted from the second data communication node. Thecontrol device comprises a control unit for outputting the informationto control the imaging device from the first data communication node, astorage unit for storing at least one or more preset imaging devicecontrol conditions, and a control condition changing unit for changingthe imaging device control conditions stored in the storage unit. Adetecting unit is provided for detecting whether the control device andthe imaging device are connected, and an output unit is started up inresponse to a detection signal from the detecting unit for reading theimaging device control conditions stored in the storage unit andoutputting the read control conditions from the first data communicationnode.

[0174] In the above imaging device system according to the presentinvention, the control device may further comprise a display unit fordisplaying an image corresponding to the imaging device controlconditions changed by the control condition changing unit.

[0175] Also, the present invention provides an imaging device systemcomprising a control device having a first data communication node, anda plurality of imaging devices having second to N-th (N is an integernot less than three) data communication nodes connected to the firstdata communication node in a mutually communicable manner. The pluralityof imaging devices include controlled units capable of being externallycontrolled in accordance with information inputted respectively from thesecond to N-th data communication nodes. The control device comprises acontrol unit for outputting the information to control the plurality ofimaging devices individually from the first data communication node, afirst storage unit for storing at least one or more imaging devicecontrol conditions preset corresponding to each of the plurality ofimaging devices, and a selecting unit for selecting one among theplurality of imaging devices which is to be controlled. A controlcondition changing unit is provided for changing the imaging devicecontrol conditions stored in the first storage unit and corresponding tothe imaging device selected by the selecting unit. A detecting unit isprovided for detecting whether the control device and the selectedimaging device are connected, and an output unit started up in responseto a detection signal from the detecting unit for reading the imagingdevice control conditions changed by the control condition changing unitand outputting the read control conditions from the first datacommunication node.

[0176] In the above imaging device system according to the presentinvention, the control device may further comprise a display unit fordisplaying an image corresponding to the imaging device controlconditions changed by the control condition changing unit.

[0177] In the above imaging device system according to the presentinvention, the selecting unit may select a particular one among theplurality of connected imaging devices by outputting an ID numberspecific to the particular imaging device from the first datacommunication node.

[0178] Further, the present invention provides an imaging device systemcomprising a control device having a first data communication node, andan imaging device having a second data communication node connected tothe first data communication node in a mutually communicable manner. Theimaging device comprises a controlled unit capable of being externallyset to a particular state in accordance with a command inputted from thesecond data communication node, and a transmitting unit capable ofexternally transmitting the particular set state. The control devicecomprises a control unit for outputting, from the first datacommunication node, a command to set the imaging device to a particularstate and a command to read a particular setting value in the imagingdevice, a storage unit for storing at least one or more preset imagingdevice setting values, and a display unit for displaying the storedsetting values. A detecting unit is provided for detecting whether thecontrol device and the imaging device are connected. An output unit isstarted up in response to a detection signal from the detecting unit andoutputs the command to read the particular setting value in the imagingdevice from the first data communication node. An input unit is providedfor inputting, into the storage unit, the particular setting value readin accordance with the command outputted from the output unit.

[0179] Still further, the present invention provides an imaging devicesystem comprising a control device having a first data communicationnode, and a plurality of imaging devices having second to N-th (N is aninteger not less than three) data communication nodes connected to thefirst data communication node in a mutually communicable manner. Theplurality of imaging devices includes controlled units capable of beingexternally controlled to set the plurality of imaging devices toparticular states in accordance with commands inputted respectively fromthe second to N-th data communication nodes. A transmitting unit isprovided that is capable of externally transmitting the particular setstates. The control device comprises a control unit for outputting, fromthe first data communication node, commands to individually set theplurality of imaging devices to particular states, and commands toindividually read particular setting values in the plurality of imagingdevices. A storage unit is provided for storing at least one or morepreset imaging device setting values corresponding to each of theplurality of imaging devices. A selecting unit is provided for selectingone among the plurality of imaging devices which is to be controlled. Adisplay unit is provided for displaying the stored setting valuescorresponding to the imaging device selected in the selecting step. Adetecting unit is provided for detecting whether the control device andthe selected imaging device are connected. An output unit is started upin response to a detection signal from the detecting unit, foroutputting the command to read the particular setting value in theselected imaging device from the first data communication node. An inputunit is provided for inputting, in an area of the storage unitcorresponding to the selected imaging device, the particular settingvalue read in accordance with the command outputted from the outputunit.

[0180] In the above imaging device system according to the presentinvention, the selecting unit may select a particular one among theplurality of connected imaging devices by outputting an ID numberspecific to the particular imaging device from the first datacommunication node.

[0181] The above imaging device system according to the presentinvention may further comprise a comparing unit for comparing the readparticular setting value in the imaging device with the correspondingimaging device setting value stored in the storage unit before readingthe particular setting value, and an alarm display unit started up bythe comparing unit.

[0182] Moreover, the present invention provides a control method for animaging device system comprising a control device having a first datacommunication node, and an imaging device having a second datacommunication node connected to the first data communication node in amutually communicable manner. The control method comprises a controlstep of outputting information to control the imaging device from thesecond data communication node, a storing step of storing at least oneor more preset imaging device control conditions, and a controlcondition changing step of changing the imaging device controlconditions stored in the storing step. A detecting step is provided fordetecting whether the control device and the imaging device areconnected, and an output step is provided for, in accordance with adetection result in the detecting step, reading the imaging devicecontrol conditions stored in the storing step and outputting the readcontrol conditions from the first data communication node.

[0183] Further, the present invention provides a control method for animaging device system comprising a control device having a first datacommunication node, and a plurality of imaging devices having second toN-th (N is an integer not less than three) data communication nodesconnected to the first data communication node in a mutuallycommunicable manner. The control method comprises a control step ofoutputting information to control the plurality of imaging devicesindividually from the first data communication node, a first storingstep of storing at least one or more imaging device control conditionspreset corresponding to each of the plurality of imaging devices, and aselecting step of selecting one among the plurality of imaging deviceswhich is to be controlled. A control condition changing step is providedfor changing the imaging device control conditions corresponding to theimaging device selected in the selecting step. A detecting step is alsoprovided for detecting whether the control device and the selectedimaging device are connected, and an output step is provided for, inaccordance with a detection result in the detecting step, reading theimaging device control conditions changed in the control conditionchanging step and outputting the read control conditions from the firstdata communication node.

[0184] Still further, the present invention provides a control methodfor an imaging device system comprising a control device having a firstdata communication node, and an imaging device having a second datacommunication node connected to the first data communication node in amutually communicable manner. The control method comprises a controlstep of outputting, from the first data communication node, a command toset the imaging device to a particular state and a command to read aparticular setting value in the imaging device. A first storing step isprovided for storing at least one or more preset imaging device settingvalues. A displaying step is also provided for displaying the storedsetting values, and a detecting step is provided for detecting whetherthe control device and the imaging device are connected. An output stepis provided for, in accordance with a detection result in the detectingstep, outputting the command to read the particular setting value in theimaging device from the first data communication node. A second storingstep is provided for storing the particular setting value read inaccordance with the command outputted in the output step.

[0185] Still further, the present invention provides a control methodfor an imaging device system comprising a control device having a firstdata communication node, and a plurality of imaging devices havingsecond to N-th (N is an integer not less than three) data communicationnodes connected to the first data communication node in a mutuallycommunicable manner. The control method comprises a control step ofoutputting, from the first data communication node, commands toindividually set the plurality of imaging devices to particular states,and commands to individually read particular setting values in theplurality of imaging devices. A first storing step is provided forstoring at least one or more preset imaging device setting valuescorresponding to each of the plurality of imaging devices, and aselecting step is provided for selecting one among the plurality ofimaging devices which is to be controlled. A displaying step is providedfor displaying the stored setting values corresponding to the imagingdevice selected in the selecting step, and a detecting step is providedfor detecting whether the control device and the selected imaging deviceare connected. An output step is provided for, in accordance with adetection result in the detecting step, outputting the command to readthe particular setting value in the selected imaging device from thefirst data communication node. A second storing step is provided forstoring, corresponding to the selected imaging device, the particularsetting value read in accordance with the command outputted in theoutput step.

[0186] Moreover, the present invention provides a storage medium storinga control program for controlling an imaging device system comprising acontrol device having a first data communication node, and an imagingdevice having a second data communication node connected to the firstdata communication node in a mutually communicable manner. The controlprogram comprises code for a control step of outputting information tocontrol the imaging device from the second data communication node, codefor a storing step of storing at least one or more preset imaging devicecontrol conditions, and code for a control condition changing step ofchanging the imaging device control conditions stored in the storingstep. Code is also provided for a detecting step of detecting whetherthe control device and the imaging device are connected. And code isprovided for an output step of, in accordance with a detection result inthe detecting step, reading the imaging device control conditions storedin the storing step and outputting the read control conditions from thefirst data communication node.

[0187] Further, the present invention provides a storage medium storinga control program for controlling an imaging device system comprising acontrol device having a first data communication node, and a pluralityof imaging devices having second to N-th (N is an integer not less thanthree) data communication nodes connected to the first datacommunication node in a mutually communicable manner. The controlprogram comprises code for a control step of outputting information tocontrol the plurality of imaging devices individually from the firstdata communication node, and code for a first storing step of storing atleast one or more imaging device control conditions preset correspondingto each of the plurality of imaging devices. Code is provided for aselecting step of selecting one among the plurality of imaging deviceswhich is to be controlled. Code is also provided for a control conditionchanging step of changing the imaging device control conditionscorresponding to the imaging device selected in the selecting step. Codeis provided for a detecting step of detecting whether the control deviceand the selected imaging device are connected. And code is provided foran output step of, in accordance with a detection result in thedetecting step, reading the imaging device control conditions changed inthe control condition changing step and outputting the read controlconditions from the first data communication node.

[0188] Still further, the present invention provides a storage mediumstoring a control program for controlling an imaging device systemcomprising a control device having a first data communication node, andan imaging device having a second data communication node connected tothe first data communication node in a mutually communicable manner. Thecontrol program comprises code for a control step of outputting, fromthe first data communication node, a command to set the imaging deviceto a particular state, and a command to read a particular setting valuein the imaging device. Code is also provided for a first storing step ofstoring at least one or more preset imaging device setting values. Codeis provided for a displaying step of displaying the stored settingvalues, and code is provided for a detecting step of detecting whetherthe control device and the imaging device are connected. Code is alsoprovided for an output step of, in accordance with a detection result inthe detecting step, outputting the command to read the particularsetting value in the imaging device from the first data communicationnode. And code is provided for a second storing step of storing theparticular setting value read in accordance with the command outputtedin the output step.

[0189] Still further, the present invention provides a storage mediumstoring a control program for controlling an imaging device systemcomprising a control device having a first data communication node, anda plurality of imaging devices having second to N-th (N is an integernot less than three) data communication nodes connected to the firstdata communication node in a mutually communicable manner. The controlprogram comprises code for a control step of outputting, from the firstdata communication node, commands to individually set the plurality ofimaging devices to particular states and commands to individually readparticular setting values in the plurality of imaging devices. Code isalso provided for a first storing step of storing at least one or morepreset imaging device setting values corresponding to each of theplurality of imaging devices. Code is provided for a selecting step ofselecting one among the plurality of imaging devices which is to becontrolled. Code is also provided for a displaying step of displayingthe stored setting values corresponding to the imaging device selectedin the selecting step. Code is provided for a detecting step ofdetecting whether the control device and the selected imaging device areconnected, and code is provided for an output step of, in accordancewith a detection result in the detecting step, outputting the command toread the particular setting value in the selected imaging device fromthe first data communication node. And code is provided for a secondstoring step of storing, corresponding to the selected imaging device,the particular setting value read in accordance with the commandoutputted in the output step.

[0190] Also, the present invention provides an imaging device for use inany of the imaging device systems according to the present invention.

[0191] Further, the present invention provides a control device for usein any of the imaging device systems according to the present invention.

[0192] Still further, the present invention provides a control methodimplemented in an imaging device for executing the control method forany of the imaging device systems according to the present invention.

[0193] Still further, the present invention provides a control methodimplemented in a control device for executing the control method for anyof the imaging device systems according to the present invention.

[0194] Moreover, the present invention provides an imaging device systemcomprising a control device having a first data communication node, andan imaging device having a second data communication node connected tothe first data communication node in a mutually communicable manner.When the imaging device and the control device are connected, eitherimaging device control conditions set on the imaging device side orimaging device control conditions set on the control device side are setto both the imaging device and the control device.

[0195] Further, the present invention provides a control method for animaging device system comprising a control device having a first datacommunication node, and an imaging device having a second datacommunication node connected to the first data communication node in amutually communicable manner. When the imaging device and the controldevice are connected, either imaging device control conditions set onthe imaging device side or imaging device control conditions set on thecontrol device side are set to both the imaging device and the controldevice.

[0196] Still further, the present invention provides a storage mediumstoring a control program for controlling an imaging device systemcomprising a control device having a first data communication node, andan imaging device having a second data communication node connected tothe first data communication node in a mutually communicable manner. Thecontrol program includes code for a step of, when the imaging device andthe control device are connected, setting either imaging device controlconditions set on the imaging device side or imaging device controlconditions set on the control device side to both the imaging device andthe control device.

BRIEF DESCRIPTION OF THE DRAWINGS

[0197]FIG. 1 is a block diagram showing a configuration of a firstembodiment.

[0198]FIG. 2 is a flowchart for explaining the first embodiment.

[0199]FIG. 3 is a flowchart for explaining a second embodiment.

[0200]FIG. 4 is a block diagram showing a configuration of the secondembodiment.

[0201]FIG. 5 shows a screen display in the second embodiment.

[0202]FIG. 6 is a block diagram showing a configuration of a thirdembodiment.

[0203]FIG. 7 is a diagram showing one example of a network systemconstructed by using 1394 serial buses (in conformity with IEEE 1394).

[0204]FIG. 8 is a diagram showing components of the 1394 serial bus (inconformity with IEEE 1394).

[0205]FIG. 9 is a diagram showing an address space in the 1394 serialbus (in conformity with IEEE 1394).

[0206]FIG. 10 is a sectional view of a 1394 serial bus cable.

[0207]FIG. 11 is a chart for explaining a DS-Link coding method for adata transfer format (in conformity with IEEE 1394).

[0208]FIG. 12 is a diagram showing one example of an actual network (inconformity with IEEE 1394).

[0209]FIGS. 13A and 13B are diagrams for explaining processes ofrequesting the use of the bus and permitting the use of the bus.

[0210]FIG. 14 is a chart showing state transition over time duringasynchronous transfer (in conformity with IEEE 1394).

[0211]FIG. 15 shows an example of a packet format for use in theasynchronous transfer mode (in conformity with IEEE 1394).

[0212]FIG. 16 is a chart showing state transition over time duringisochronous transfer (in conformity with IEEE 1394).

[0213]FIG. 17 shows an example of a packet format for use in theisochronous transfer mode (in conformity with IEEE 1394).

[0214]FIG. 18 is a chart showing transfer state transition on the busover time when an isochronous transfer and an asynchronous transfer areexecuted in mixed fashion (in conformity with IEEE 1394).

[0215]FIG. 19 is a flowchart showing a general sequence 1 from a busreset to a decision of node IDs (in conformity with IEEE 1394).

[0216]FIG. 20 is a flowchart showing a general sequence 2 from a busreset to a decision of node IDs (in conformity with IEEE 1394).

[0217]FIG. 21 is a flowchart showing a general sequence from a bus resetto a decision of node IDs (in conformity with IEEE 1394).

[0218]FIG. 22 is a flowchart showing a sequence of an arbitrationprocess (in conformity with IEEE 1394).

[0219]FIG. 23 shows address locations in a configuration ROM.

[0220]FIG. 24 shows screen display 1 in the related art.

[0221]FIG. 25 shows a PC and a video camera connected to each other inthe related art.

[0222]FIG. 26 shows screen display 2 in the related art.

[0223]FIG. 27 shows screen display 3 in the related art.

[0224]FIG. 28 is a table showing examples of camera setting commands.

[0225]FIG. 29 is a flowchart showing the third embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0226] Preferred embodiments of the present invention will be describedbelow in detail with reference to the accompanying drawings.

[0227] (First Embodiment)

[0228]FIG. 1 is a block diagram showing a configuration of a firstembodiment. A video camera 1A and a personal computer (PC) 1B areconnected to each other by a 1394 serial bus cable 108.

[0229] Describing first a block on the video camera 1A side, numeral 101denotes a lens, and 102 denotes a signal processing unit which includesan image pickup device for converting light inputted through the lens101 into an image signal, and which converts the image signal outputtedfrom the image pickup device into a digital image signal. Numeral 103denotes a control unit for controlling the entirety of the video camera,and 104 denotes one or more camera control parameters read by thecontrol unit 103 for controlling the lens 101 and the signal processingunit 102 to produce the digital image signal. Numeral 105 denotes adigital interface for receiving and outputting the digital image signal,various control information, etc. via the 1394 serial bus 108, and 106denotes a volatile memory from and into which data is read and writtenby the control unit 103, the volatile memory temporarily storing camerasetting values, etc. which are inputted from the digital interface 105.Numeral 107 denotes a non-volatile memory from and into which data isread and written by the control unit 103, the non-volatile memoryfinally storing the camera setting values, etc. which are inputted fromthe digital interface 105.

[0230] Next, a block on the PC 1B side will be described.

[0231] Numeral 109 denotes a digital interface for receiving the digitalimage from the video camera 1A via the 1394 serial bus 108 andoutputting various command data, etc. from a control unit 112 to the1394 serial bus 108, and 110 denotes a connection detector for detectingwhether the video camera is connected to the 1394 serial bus 108.Numeral 111 denotes a user operating panel, such as a keyboard or apointing device, through which the user operates the PC, and 112 denotesa control unit for controlling the entirety of the PC. Numeral 113denotes one or more camera setting parameters read, written and changedby the control unit 112 in accordance with an input from the useroperating panel 111, and 114 denotes a hard disk for storing the camerasetting parameters 113 in the form of a file. Numeral 115 denotes animage processing unit which includes an image memory for storing thedigital image information inputted from the video camera 1A via thedigital interface 109, and which can apply a digital effect to the imagein the memory upon receiving a command from the control unit 112.Numeral 116 denotes an image display unit for producing a window displayimage based on the digital image information outputted from the imageprocessing unit 115 and the camera setting parameters, and outputtingthe produced image to a monitor 117.

[0232] The video camera 1A receives the camera setting parameters and acommand, such as “Set” or “Write”, from the digital interface 105, andcarries out an internal operation corresponding to the command.Specifically, when the camera setting parameters and the command “Set”are inputted, the control unit 103 sets the inputted parameters in thevolatile memory 106, and controls the lens 101 and the signal processingunit 102 by using those parameters temporarily. Also, when the camerasetting parameters and the command “Write” are inputted, the controlunit 103 writes the inputted parameters in both the volatile memory 106and the non-volatile memory 107, and controls the lens 101 and thesignal processing unit 102 by using those parameters after that. Here,the inputted camera setting parameters mean setting values of parameterscapable of controlling the lens and the signal processing system tochange the output image, such as tint, color gain, f-stop number andshutter speed, as described above in connection with the related art.

[0233] The operation of a camera setting application on the PC side inthe first embodiment will be described below in more detail withreference to a flowchart of FIG. 2. The camera setting applicationpresents the same screen display as shown in FIG. 24.

[0234] Also, as described above in connection with the related art, asimulation mode in this embodiment means a mode in which the user canchange the camera setting parameters in the PC even with the PC notconnected to the video camera, and can confirm an image resulted fromthe parameter change on the monitor screen. Further, a camera mode inthis embodiment means a mode in which the user can actually change thecamera setting parameters in the video camera with the video cameraconnected to the PC, while confirming an image transmitted from thevideo camera, thereby optimizing the image. By manipulating an operatingmode select button 2407 on the screen with the pointing device or thelike through the user operating panel 111, the camera settingapplication can be switched over between the simulation mode and thecamera mode at the user's discretion.

[0235] Upon start-up of the camera setting application, a program isfirst started in the simulation mode in step S1201.

[0236] Then, it is checked in step S1202 whether the mode is switchedover to the camera mode. If not switched over, the control unit enters asimulation mode process in step S1207. In the simulation mode process,the control unit executes such operations as receiving an input from theuser operating panel 111, outputting a command to the image processingunit 115 corresponding to a changed one of the camera setting parameters113, controlling the image display unit 116 to switch over the monitorscreen, and storing the camera setting parameters 113 in the hard disk114 in the form of a file.

[0237] At a breakpoint during the simulation mode process, it is checkedagain in step S1208 whether the mode is switched over to the cameramode. If not switched over, the simulation mode process is resumed instep S1207.

[0238] If switched over, it is checked in step S1203 whether the videocamera is connected, by referring to the connection detector 110. If notconnected, the control unit returns to step S1202 again to repeat a loopprocess while it is on standby for the next operation.

[0239] If connected, one or more of the camera setting parameters 113(which have been changed by simulation) are outputted in step S1204 fromthe digital interface 109, thereby changing the corresponding camerasetting parameters in the video camera connected to the PC. In otherwords, a data match is established between the PC and the video cameraconnected to the PC at the time when the video camera is initiallyconnected. Then, a step S1205 a camera adjustment process is executedwith the matched state being as an initial state.

[0240] In the camera adjustment process, the control unit executes suchoperations as receiving an input from the user operating panel 111,outputting a parameter and a command from the digital interface 109corresponding to changed one of the camera setting parameters 113,displaying a screen of the image data transmitted from the video camera,and storing the camera setting parameters 113 in the hard disk 114 inthe form of a file. At a breakpoint during the camera adjustmentprocess, it is checked again in step S1206 whether the mode is switchedover to the simulation mode. If not switched over, the control unitreturns to step S1205 again to resume the camera adjustment process, andif switched over, it goes to step S1207 for shift to the simulationprocess.

[0241] With the control procedures described above, a data match betweenthe PC and the video camera can be obtained in an initial conditionwhere the camera is connected to the PC. It is therefore possible toavoid such trouble as causing a contradiction in the subsequent process.

[0242] (Second Embodiment)

[0243]FIG. 3 is a flowchart of a camera setting application forexplaining the second embodiment of the present invention. The controlshown in FIG. 3 is executed with a configuration shown in a blockdiagram of FIG. 4. The second embodiment will be described below withreference to FIGS. 3 and 4.

[0244] Upon start-up of the camera setting application, a program isfirst started in the simulation mode in step S1301.

[0245] Then, it is checked in step S1302 whether the mode is switchedover to the camera mode. If not switched over, the control unit enters asimulation mode process in step S1309. In the simulation mode process,the control unit executes such operations as receiving an input from theuser operating panel 111, outputting a command to the image processingunit 115 corresponding to a changed one of the camera setting parameters113, controlling the image display unit 116 to switch over the monitorscreen, and storing the camera setting parameters 113 in the hard disk114 in the form of a file.

[0246] At a breakpoint during the simulation mode process, it is checkedagain in step S1310 whether the mode is switched over to the cameramode. If not switched over, the simulation mode process is resumed instep S1309.

[0247] If switched over, it is checked in step S1303 whether the videocamera is connected, by referring to the connection detector 110. If notconnected, the control unit returns to step S1302 again to repeat a loopprocess while it is on standby for the next operation. The processing sofar described is exactly the same as in the first embodiment.

[0248] If it is detected in step S1303 that the video camera isconnected, the control unit 112 issues a command to read the camerasetting parameters, such as tint, color gain, f-stop number and shutterspeed, to the video camera via the digital interface 109. Upon receivingthe command, the control unit 103 in the video camera read requests oneor more of the camera setting parameters from the volatile memory 106 orthe non-volatile memory 107, and transmits the read data to the PC viathe digital interface 105. Through the above procedures, the controlunit 112 on the PC side reads the above parameters in the video cameraconnected to the PC, and then stores them as camera-side read parameters118 on the PC side.

[0249] Next, in step S1305, the control unit 112 compares thecamera-side read parameters 118 and the camera setting parameters 113currently existing in the PC. Depending on a compared result, in stepS1306, the control unit 112 displays the camera setting parameters on ascreen image of the camera setting application. Specifically, if thecompared result shows a discrepancy in data values between the videocamera and the PC, the control unit 112 issues an alarm.

[0250]FIG. 5 shows a screen image of the camera setting applicationwhich includes an alarm display produced through the above-describedprocedures. The screen image of FIG. 5 illustrates an example in whichthe shutter speed value differs between the video camera and the PC. Inthis case, the shutter speed display is highlighted as indicated by 501.Furthermore, in this embodiment, a subwindow 502 for prompting the userto select a subsequent process is additionally displayed.

[0251] After that, the control unit 112 enters a camera adjustmentprocess in a step S1307. If the alarm display described above isproduced, the control unit 112 receives an input from the user. In otherwords, the user selects one of two buttons on the subwindow 502 by usingthe user operating panel 111 in the form of, e.g., a pointing device,thereby deciding with which data two different data should be matched.

[0252] If the button indicating “SET TO CAMERA SIDE SPEED” is selected,the control unit 112 rewrites a corresponding one of the camera settingparameters 113 to the value of the corresponding camera-side readparameter 118. Conversely, if the button indicating “SET TO PC SIDESPEED” is selected, the control unit 112 rewrites a corresponding one ofthe camera-side read parameters 118 to the value of the correspondingcamera setting parameter 113, and also outputs that camera settingparameter 113 through the digital interface 109 for changing thecorresponding camera-side read parameter in the video camera connectedto the PC. As a result, a data match is established between the PC andthe video camera connected to the PC at the time when the video camerais initially connected.

[0253] (Third Embodiment)

[0254] This third embodiment intends to achieve the above-described datamatch when a plurality of devices are connected to a network accordingto one feature of the 1394 serial bus connection. This point will bedescribed below.

[0255]FIG. 6 is a block diagram showing a configuration of the thirdembodiment. Numerals 601 to 603 denote video cameras connected by the1394 serial buses, and 608 denotes a PC for setting parameters of thevideo cameras.

[0256] As described above in connection with the related art, the videocameras 601 to 603 are internally given WWUID(1) to WWUID(N) as IDswhich are used in the 1394 serial bus network and specific to therespective cameras. The PC 608 can read the WWUIDs via the 1394 serialbuses, and conversely can perform such operations as receiving imageinformation from only one of the video cameras having the particularWWUID, and producing a camera parameter setting command to the videocameras having the particular WWUID.

[0257] A camera setting application in this embodiment can hold camerasetting parameters for a plurality of video cameras, and also can selecta particular one of the plurality of video cameras connected to thenetwork by utilizing the specific WWUID so that camera parameters of theselected one video camera may be set separately.

[0258] Details of the camera setting application executed in the PC 608according to this embodiment will be described.

[0259] Numeral 609 denotes a 1394 digital interface, and 610 denotes aconnection detector receiving a particular WWUID from the control unit612 and detecting whether the video camera having particular WWUID isconnected to the network. Numeral 611 denotes a user operating panel foroperating the camera setting application, such as selecting the videocamera and changing the camera setting parameters. Numeral 612 denotes acontrol unit for controlling the entirety of the application system, anddenotes a selected VIDEO No. memory for storing the video camera numberselected from the user operating panel 611. Numeral 614 denotes a camerasetting parameter table for holding WWUIDs corresponding to the VIDEONos. and camera setting parameter groups for the corresponding videocameras. Numeral 615 denotes an image processing unit which includes animage memory for storing digital image information inputted from thevideo camera corresponding to the selected VIDEO No. via the digitalinterface 109, and which can apply a digital effect to the image in thememory upon receiving a command from the control unit 612. Numeral 616denotes an image display unit for producing a window display image basedon the digital image information outputted from the image processingunit 615 and the camera setting parameters, and outputting the producedimage to a monitor 617. Numeral 617 denotes a hard disk for storing thecamera setting parameters in the form of a file along with the WWUID ofthe selected video camera.

[0260] Processing steps executed by the control unit 612 in the camerasetting application will be described below with reference to aflowchart of FIG. 29.

[0261] First, in step S2901, the camera setting application starts aprogram in the camera mode.

[0262] Then, in step S2902, the control unit 612 reads a camera settingparameter file stored beforehand, and develops read data in the camerasetting parameter table 614.

[0263] The user now has to select from the user operating panel 611which one of read data (i.e., which one of the video cameras) is to beset. In step S2903, therefore, the control unit 612 waits for a cameraselection input from the user.

[0264] If the camera selection input is applied, processing goes to stepS2904 to store the VIDEO No. of the selected video camera in theselected VIDEO No. memory 613.

[0265] After the VIDEO No. has been decided, the control unit 612 canselect a particular one of the video cameras externally connected by the1394 serial buses by referring to the WWUID corresponding to the decidedVIDEO No. in the camera setting parameter table 614.

[0266] Then, the control unit 612 transmits the WWUID selected in stepS2905 to the connection detector 610 to detect whether the video camerahaving the selected WWUID is connected to the 1394 serial bus network.

[0267] If not connected, the control unit 612 repeats a loop processwhile it is on standby for the next operation. If connected, the controlunit 612 outputs in step S2906 the camera setting parameters, which arestored in the camera setting parameter table 614 and correspond to theselected VIDEO No., to the video camera having the selected WWUID fromthe digital interface 609. After that, the control unit 612 enters stepS2907 for a camera adjustment process, described above in connectionwith the related art, with a resultant state being as an initial state.

[0268] By outputting to the camera side one or more of the camerasetting parameters, which are possibly changed by simulation, etc. onthe PC side, after the connection of the selected video camera has beendetected through the above-described procedures, a data match isestablished between the PC and the selected video camera connected tothe PC at the time when the video camera is initially connected.

[0269] Tough not described here in detail, after the connection of theselected video camera detected in step S2905 of FIG. 29, values of thecamera setting parameters in the selected video camera may be read andthe read data may be used as first display data in the camera settingapplication as with the second embodiment. In this case, it is of coursepossible to compare the parameters read from the video camera with thecamera setting parameters which are stored in the camera settingparameter table 614 and correspond to the selected VIDEO No., and toproduce an alarm display in a manner like the second embodiment if thecompared data differ from each other.

[0270] (Other Embodiments)

[0271] It is needless to say that the object of the present inventioncan also be achieved by supplying, to a system or apparatus, a storagemedium which stores program codes of software for realizing thefunctions of any of the above-described embodiments, and causing acomputer (or CPU and/or MPU) in the system or apparatus to read andexecute the program codes stored in the storage medium.

[0272] In such a case, the program codes read out of the storage mediumserve in themselves to realize the functions of any of theabove-described embodiments, and hence the storage medium storing theprogram codes comprises the present invention.

[0273] Storage mediums for use in supplying the program codes may be,e.g., floppy disks, hard disks, optical disks, magneto-optic disks,CD-ROMs, CD-Rs, magnetic tapes, nonvolatile memory cards, and ROMs.

[0274] Also, it is a matter of course that the functions of any of theabove-described embodiments is realized by not only a computer readingand executing the program codes, but also an OS (Operating System) orthe like which is working on the computer and executes part or whole ofthe actual process to realize the functions in accordance withinstructions from the program codes.

[0275] Further, it is a matter of course that the present inventioninvolves such a case where the program codes read out of the storagemedium are written into a memory provided in a function add-on boardmounted in the computer or a function add-on unit connected to thecomputer, and a CPU or the like incorporated in the function add-onboard or unit executes part or whole of the actual process in accordancewith instructions from the program codes, thereby realizing the functionof any of the above-described embodiments.

[0276] It should be understood that the present invention is alsoapplicable to various alterations or modifications of theabove-described embodiments without departing from the scope of theinvention.

[0277] For example, while a video camera is employed as the imagingdevice in the above-described embodiments, the present invention is notlimited to the embodiments, but also applicable to other types ofimaging devices such as a digital camera, a silver salt camera, and ascanner.

[0278] While data is transmitted from the control device side to theimaging device side in the above-described embodiments, data may betransmitted from the imaging device side to the control device side in areverse direction.

[0279] According to the present invention, as described above, in acamera setting system comprising a control device such as a PC and avideo camera which are connected to each other, a mismatch betweensetting values on the PC side and camera setting values in the videocamera which occurred immediately after the connection therebetween canbe automatically avoided immediately after the PC and the video cameraare connected again.

[0280] Also, in a camera setting system wherein a control device, suchas a PC, and a video camera are connected to each other, particularly ina camera setting system having a simulation function, a mismatch betweensetting values on the PC side, which have been changed upon execution ofa simulation, and unchanged setting values in the video camera can beautomatically avoided immediately after the PC and the video camera areconnected again.

[0281] Further, in a camera setting system wherein a control device,such as a PC, and a plurality of video cameras are connected to eachother, a mismatch between setting values on the PC side, whichcorrespond to a particular one of the video cameras, and camera settingvalues in the particular video camera immediately after the connectiontherebetween can be avoided.

[0282] Further, in a camera setting system wherein a control device,such as a PC, and a plurality of video cameras are connected to eachother, particularly in a camera setting system having a simulationfunction, a mismatch between setting values on the PC side, which havebeen changed upon execution of the simulation, and unchanged settingvalues in a particular one of the video cameras can be automaticallyavoided immediately after the PC and the particular video camera areconnected again.

[0283] Further, in a camera setting system wherein a control device,such as a PC, and a plurality of video cameras are connected to eachother, a particular one of the video cameras can be surely selected byutilizing IDs specific to the video cameras, and a mismatch betweensetting values on the PC side, which have been changed and correspond tothe selected video camera, and camera setting values in the selectedvideo camera can be automatically avoided.

[0284] Further, in a camera setting system wherein a control device,such as a PC, and a video camera are connected to each other, a mismatchbetween a display of setting values on the PC side and camera settingvalues in the video camera immediately after the connection therebetweencan be avoided.

[0285] Further, in a camera setting system wherein a control device,such as a PC, and a plurality of video cameras are connected to eachother, a mismatch between a display of setting values on the PC side,which correspond to a particular one of the video cameras, and camerasetting values in the particular video camera immediately after theconnection therebetween can be avoided.

[0286] Further, in a camera setting system wherein a control device,such as a PC, and a plurality of video cameras are connected to eachother, a particular one of the video cameras can be surely selected byutilizing IDs specific to the video cameras, and a mismatch between adisplay of setting values on the PC side, which correspond to theparticular video camera, and camera setting values in the selected videocamera immediately after the connection therebetween can be avoided.

[0287] Further, when setting values on the PC side, which correspond toa particular video camera, differ from camera setting values in aselected video camera, an alarm display is produced.

What is claimed is:
 1. An imaging device system comprising: a controldevice having a first data communication node; and an imaging devicehaving a second data communication node connected to said first datacommunication node in a mutually communicable manner, said imagingdevice including controlled means capable of being externally controlledin accordance with information inputted from said second datacommunication node, said control device including (i) control means foroutputting the information to control said imaging device from saidfirst data communication node, (ii) storage means for storing at leastone preset imaging device control condition, (iii) control conditionchanging means for changing said imaging device control condition storedin said storage means, (iv) detecting means for detecting whether saidcontrol device and said imaging device are connected, and (v) outputmeans started up in response to a detection signal from said detectingmeans for reading said imaging device control condition stored in saidstorage means and outputting the read control condition from said firstdata communication node.
 2. An imaging device system according to claim1, wherein said control device further comprises display means fordisplaying an image corresponding to said imaging device controlconditions changed by said control condition changing means.
 3. Animaging device system comprising: a control device having a first datacommunication node; and a plurality of imaging devices having second toN-th (N is an integer not less than three) data communication nodesconnected to said first data communication node in a mutuallycommunicable manner, said plurality of imaging devices includingcontrolled means capable of being externally controlled in accordancewith information inputted respectively from said second to N-th datacommunication nodes, said control device including (i) control means foroutputting the information to control said plurality of imaging devicesindividually from said first data communication node, (ii) first storagemeans for storing at least one imaging device control condition presetcorresponding to each of said plurality of imaging devices, (iii)selecting means for selecting one among said plurality of imagingdevices which is to be controlled, (iv) control condition changing meansfor changing said imaging device control condition stored in said firststorage means and corresponding to the imaging device selected by saidselecting means, (v) detecting means for detecting whether said controldevice and said selected imaging device are connected, and (vi) outputmeans started up in response to a detection signal from said detectingmeans for reading said imaging device control condition changed by saidcontrol condition changing means and outputting the read controlconditions from said first data communication node.
 4. An imaging devicesystem according to claim 3, wherein said control device furthercomprises display means for displaying an image corresponding to saidimaging device control condition changed by said control conditionchanging means.
 5. An imaging device system according to claim 3,wherein said selecting means selects a particular one among saidplurality of connected imaging devices by outputting an ID numberspecific to the particular imaging device from said first datacommunication node.
 6. An imaging device system comprising: a controldevice having a first data communication node; and an imaging devicehaving a second data communication node connected to said first datacommunication node in a mutually communicable manner, said imagingdevice including (i) controlled means capable of being externally set toa particular state in accordance with a command inputted from saidsecond data communication node, and (ii) transmitting means capable ofexternally transmitting said particular set state, said control deviceincluding (i) control means for outputting, from said first datacommunication node, a command to set said imaging device to a particularstate and a command to read a particular setting value in said imagingdevice, (ii) storage means for storing at least one preset imagingdevice setting value, (iii) display means for displaying said storedsetting value, (iv) detecting means for detecting whether said controldevice and said imaging device are connected, (v) output means startedup in response to a detection signal from said detecting means foroutputting the command to read said particular setting value in saidimaging device from said first data communication node, and (vi) inputmeans for inputting, in said storage means, said particular settingvalue read in accordance with the command outputted from said outputmeans.
 7. An imaging device system comprising: a control device having afirst data communication node; and a plurality of imaging devices havingsecond to N-th (N is an integer not less than three) data communicationnodes connected to said first data communication node in a mutuallycommunicable manner, said plurality of imaging devices including (i)controlled means capable of being externally controlled to set saidplurality of imaging devices to particular states in accordance withcommands inputted respectively from said second to N-th datacommunication nodes, and (ii) transmitting means capable of externallytransmitting said particular set states, said control device including(i) control means for outputting, from said first data communicationnode, commands to individually set said plurality of imaging devices toparticular states and commands to individually read particular settingvalues in said plurality of imaging devices, (ii) storage means forstoring at least one preset imaging device setting value correspondingto each of said plurality of imaging devices, (iii) selecting means forselecting one among said plurality of imaging devices which is to becontrolled, (iv) display means for displaying said stored setting valuecorresponding to the imaging device selected in said selecting step, (v)detecting means for detecting whether said control device and saidselected imaging device are connected, (vi) output means started up inresponse to a detection signal from said detecting means for outputtingthe command to read said particular setting value in said selectedimaging device from said first data communication node, and (vii) inputmeans for inputting, in an area of said storage means corresponding tosaid selected imaging device, said particular setting value read inaccordance with the command outputted from said output means.
 8. Animaging device system according to claim 7, wherein said selecting meansselects a particular one among said plurality of connected imagingdevices by outputting an ID number specific to the particular imagingdevice from said first data communication node.
 9. An imaging devicesystem according to claim 7, further comprising: comparing means forcomparing said read particular setting value in the imaging device withthe corresponding imaging device setting value stored in said storagemeans before reading said particular setting value; and alarm displaymeans started up by said comparing means.
 10. An imaging device for usein the imaging device system according to any one of claims 1 to
 9. 11.A control device for use in the imaging device system according to anyone of claims 1 to
 9. 12. A control method for an imaging device systemhaving (i) a control device with a first data communication node, and(ii) an imaging device having a second data communication node connectedto said first data communication node in a mutually communicable manner,said control method comprising the steps of: a control step ofoutputting information to control said imaging device from said seconddata communication node, a storing step of storing at least one presetimaging device control condition, a control condition changing step ofchanging said imaging device control condition stored in said storingstep, a detecting step of detecting whether said control device and saidimaging device are connected, and an output step of, in accordance witha detection result in said detecting step, reading said imaging devicecontrol condition stored in said storing step and outputting the readcontrol conditions from said first data communication node.
 13. Acontrol method for an imaging device system having (i) a control devicewith a first data communication node, and (ii) a plurality of imagingdevices having second to N-th (N is an integer not less than three) datacommunication nodes connected to said first data communication node in amutually communicable manner, said control method comprising the stepsof: a control step of outputting information to control said pluralityof imaging devices individually from said first data communication node,a first storing step of storing at least one imaging device controlcondition preset corresponding to each of said plurality of imagingdevices, a selecting step of selecting one among said plurality ofimaging devices which is to be controlled, a control condition changingstep of changing said imaging device control condition corresponding tothe imaging device selected in said selecting step, a detecting step ofdetecting whether said control device and said selected imaging deviceare connected, and an output step of, in accordance with a detectionresult in said detecting step, reading said imaging device controlcondition changed in said control condition changing step and outputtingthe read control conditions from said first data communication node. 14.A control method for an imaging device system having (i) a controldevice with a first data communication node, and (ii) an imaging devicehaving a second data communication node connected to said first datacommunication node in a mutually communicable manner, said controlmethod comprising the steps of: a control step of outputting, from saidfirst data communication node, a command to set said imaging device to aparticular state and a command to read a particular setting value insaid imaging device, a first storing step of storing at least one presetimaging device setting value, a displaying step of displaying saidstored setting value, a detecting step of detecting whether said controldevice and said imaging device are connected, an output step of, inaccordance with a detection result in said detecting step, outputtingthe command to read said particular setting value in said imaging devicefrom said first data communication node, and a second storing step ofstoring said particular setting value read in accordance with thecommand outputted in said output step.
 15. A control method for animaging device system having (i) a control device with a first datacommunication node, and (ii) a plurality of imaging devices havingsecond to N-th (N is an integer not less than three) data communicationnodes connected to said first data communication node in a mutuallycommunicable manner, said control method comprising the steps of: acontrol step of outputting, from said first data communication node,commands to individually set said plurality of imaging devices toparticular states and commands to individually read particular settingvalues in said plurality of imaging devices, a first storing step ofstoring at least one preset imaging device setting value correspondingto each of said plurality of imaging devices, a selecting step ofselecting one among said plurality of imaging devices which is to becontrolled, a displaying step of displaying said stored setting valuecorresponding to the imaging device selected in said selecting step, adetecting step of detecting whether said control device and saidselected imaging device are connected, an output step of, in accordancewith a detection result in said detecting step, outputting the commandto read said particular setting value in said selected imaging devicefrom said first data communication node, and a second storing step ofstoring, corresponding to said selected imaging device, said particularsetting value read in accordance with the command outputted in saidoutput step.
 16. A control method implemented in an imaging device forexecuting the control method for the imaging device system according toany one of claims 12 to
 15. 17. A control method implemented in acontrol device for executing the control method for the imaging devicesystem according to any one of claims 12 to
 15. 18. A storage mediumstoring a computer-readable control program for controlling an imagingdevice system having (i) a control device with a first datacommunication node, and (ii) an imaging device having a second datacommunication node connected to said first data communication node in amutually communicable manner, said control program comprising thefollowing computer-readable code: code for a control step of outputtinginformation to control said imaging device from said second datacommunication node, code for a storing step of storing at least onepreset imaging device control condition, code for a control conditionchanging step of changing said imaging device control condition storedin said storing step, code for a detecting step of detecting whethersaid control device and said imaging device are connected, and code foran output step of, in accordance with a detection result in saiddetecting step, reading said imaging device control condition stored insaid storing step and outputting the read control conditions from saidfirst data communication node.
 19. A storage medium storing acomputer-readable control program for controlling an imaging devicesystem having (i) a control device with a first data communication node,and (ii) a plurality of imaging devices having second to N-th (N is aninteger not less than three) data communication nodes connected to saidfirst data communication node in a mutually communicable manner, saidcontrol program comprising the following computer-readable code: codefor a control step of outputting information to control said pluralityof imaging devices individually from said first data communication node,code for a first storing step of storing at least one imaging devicecontrol condition preset corresponding to each of said plurality ofimaging devices, code for a selecting step of selecting one among saidplurality of imaging devices which is to be controlled, code for acontrol condition changing step of changing said imaging device controlcondition corresponding to the imaging device selected in said selectingstep, code for a detecting step of detecting whether said control deviceand said selected imaging device are connected, and code for an outputstep of, in accordance with a detection result in said detecting step,reading said imaging device control condition changed in said controlcondition changing step and outputting the read control condition fromsaid first data communication node.
 20. A storage medium storing acomputer-readable control program for controlling an imaging devicesystem having (i) a control device with a first data communication node,and (ii) an imaging device having a second data communication nodeconnected to said first data communication node in a mutuallycommunicable manner, said control program comprising the followingcomputer-readable code: code for a control step of outputting, from saidfirst data communication node, a command to set said imaging device to aparticular state and a command to read a particular setting value insaid imaging device, code for a first storing step of storing at leastone preset imaging device setting value, code for a displaying step ofdisplaying said stored setting value, code for a detecting step ofdetecting whether said control device and said imaging device areconnected, code for an output step of, in accordance with a detectionresult in said detecting step, outputting the command to read saidparticular setting value in said imaging device from said first datacommunication node, and code for a second storing step of storing saidparticular setting value read in accordance with the command outputtedin said output step.
 21. A storage medium storing a computer-readablecontrol program for controlling an imaging device system having (i) acontrol device with a first data communication node, and (ii) aplurality of imaging devices having second to N-th (N is an integer notless than three) data communication nodes connected to said first datacommunication node in a mutually communicable manner, said controlprogram comprising the following computer-readable code: code for acontrol step of outputting, from said first data communication node,commands to individually set said plurality of imaging devices toparticular states and commands to individually read particular settingvalues in said plurality of imaging devices, code for a first storingstep of storing at least one preset imaging device setting valuecorresponding to each of said plurality of imaging devices, code for aselecting step of selecting one among said plurality of imaging deviceswhich is to be controlled, code for a displaying step of displaying saidstored setting value corresponding to the imaging device selected insaid selecting step, code for a detecting step of detecting whether saidcontrol device and said selected imaging device are connected, code foran output step of, in accordance with a detection result in saiddetecting step, outputting the command to read said particular settingvalue in said selected imaging device from said first data communicationnode, and code for a second storing step of storing, corresponding tosaid selected imaging device, said particular setting value read inaccordance with the command outputted in said output step.
 22. Animaging device system comprising: a control device having a first datacommunication node; and an imaging device having a second datacommunication node connected to said first data communication node in amutually communicable manner, wherein: when said imaging device and saidcontrol device are connected, either imaging device control conditionsset on the imaging device side or imaging device control conditions seton the control device side are set to both said imaging device and saidcontrol device.
 23. A control method for an imaging device system having(i) a control device with a first data communication node, and (ii) animaging device with a second data communication node connected to saidfirst data communication node in a mutually communicable manner,wherein: when said imaging device and said control device are connected,either imaging device control conditions set on the imaging device sideor imaging device control conditions set on the control device side areset to both said imaging device and said control device.
 24. A storagemedium storing a computer-readable control program for controlling animaging device system having (i) a control device having a first datacommunication node, and (ii) an imaging device having a second datacommunication node connected to said first data communication node in amutually communicable manner, wherein: said control program includescomputer-readable code for a step of, when said imaging device and saidcontrol device are connected, setting either imaging device controlconditions set on the imaging device side or imaging device controlconditions set on the control device side to both said imaging deviceand said control device.